Re: Re: What does Tool Radius Compensation do ?

PTENGIN@... wrote:

> From: PTENGIN@...
>
> In a message dated 11/07/1999 10:46:53 AM Hawaiian Standard Time,
> drewid@... writes:
>
> << Your program (toolpath) must activate it, and you must have already entered
> a radius (or diameter, usually) for a specific tool into the CNC's tool
> table.
> It allows tools of somewhat different diameter to be used without changing
> the
> program. The CNC has to know which side of the specified line to cut on.
> The toolpath is specified as the actual dimension of the part, and is not
> offset
> by the tool radius, as you would usually do when writing G-code by hand
> or with a CAD/CAM program. >>
>
> Andrew,
> In this particular instance, I think the only thing that needs to be
> addressed is whether you cutter comp off a flat xy plane or off the rotary A
> axis. Cutter comp must take place with your rotary table centerline axis
> being your zero point rather than a flat surface. This may be the reason the
> three panels don't line up.

Right, very good point. The Y=0 must be set with the spindle centered
exactly over the rotational axis of the index head, and the rotational axis of the
index head must be accurately parallel to the X axis travel. Also, the Z axis
must be zeroed at some known distance above the rotary axis (could be zero,
exactly ON the rotary axis, too). Whatever is consistant with the way the part
coordinates were layed out on the drawing.

Jon